Japan is an archipelagic country composed of the four large islands of Hokkaido, Honshu, Shikoku, and Kyushu as well as more than 6,800 smaller islands. Its landscape is overwhelmingly composed of mountains and valleys, with more than three-quarters of the land area consisting of mountains. Ice and snow from these mountains has created a large number of rivers, which play an important role in the country’s transportation, irrigation, and electricity generation.
The rivers of Japan are generally characterised as short, steep and fast-flowing. This makes them excellent generators of hydroelectric power, but also entails a high likelihood of flooding. Despite the flood risks, Japanese settlements have grown around rivers since ancient times. Many of these rivers have been modified, some quite significantly, to account for this.
Under the River Law of 1967, Japan waterways and rivers are classified as either Class A or Class B systems. Most of the best known rivers Japan has to offer fall under Class A, meaning they are deemed of economic or ecological importance to the nation.
1. Shinano River (Shinanogawa)
The Shinano River or “Shinanogawa” on the island of Honshu is famed as the longest of all rivers in Japan. The river flows north for approximately 228 miles from its source at Mount Kobushi in the Japanese Alps to its mouth in the Sea of Japan. Along its course, the Shinano River passes through some of the country’s most populous regions and several major cities, including Matsumoto, Nagano, and Niigata.
The Shinano River has been an important part of Japanese life for centuries. It has served as a source of drinking water, a transportation route, and a place for recreation and relaxation. Perhaps its most well-known use is that of providing hydro-electricity. Indeed, the country’s first ever such power plant, The Miyashiro No. 1 power plant, was established along the river in 1904 and is still in use today.
The river is home to a diverse array of plant and animal life as well as a variety of fish, among them Cherry Salmon. In the summer, the Shinano River is a popular spot for swimming and fishing, and in the winter, the river is popular for ice skating and ice fishing. There are also many popular Onsen, or hot springs, along the river.
2. Tone River (Tonegawa)
The Tone or “Tonegawa” River is one of the most important rivers of Japan. This is largely down to its location, flowing as it does through the highly populous region of the Kanto Plain. The river has its origins in the mountains of central Japan and stretches some 200 miles to the Pacific Ocean.
Some 40 million people live within the river’s catchment, the largest in Japan at approximately 6,540 square miles. Not only is this in the centre of the country, but also on its largest plain and home to its capital, Tokyo.
Whereas it’s said that Tonegawa was once a wild and uncontrollable waterway, many now consider it the most artificially altered of all Japanese rivers. Indeed its current route bears little resemblance to its ancient one.
Today, Tonegawa has several dams, creating reservoirs as a source of both residential and agricultural water for the Kanto region. The largest of these is the Yagisawa Dam. The river is also used for transportation and recreation and is bordered by Japan’s longest car free cycling path.
3. Ishikari River (Ishikarigawa)
Travelling some 167 miles from Mount Ishikari to the Sea of Japan, the Ishikari River is the longest river in the state of Hokkaido and third longest in Japan. It serves as a major source of water for the city of Sapporo, through which it flows. The river is also a popular spot for fishing, swimming, and canoeing. It’s home to a variety of fish, including trout, carp, and eel.
4. Teshio River (Teshiogawa)
Japan’s northernmost major river is the Teshio or “Teshigahara” in Hokkaido. Fed by Mount Teshio of the Kitami Mountains, it flows for approximately 159 miles and its basin is about 2,160 square miles in size. The average discharge of the river is an estimated 9,000 cubic feet per second.
The Teshio River has been an important trade and transportation route since ancient times, used as such by the indigenous Ainu people. The river remains a vital source of irrigation and hydroelectric power generation.
5. Kitakami River (Kitakamigawa)
A vital transportation route during the Edo period, the Kitakami River is the longest river in the Tohoku region and is approximately 155 miles long. It’s considered to be one of the most scenic rivers of Japan, known for its abundance of cherry blossoms in the springtime. The Kitakami is also home to many different species of fish and is a popular spot for fishing.
5. Niyodo River
Located on the island of Shikoku in Kōchi Prefecture, the Niyodo River is famed for its extraordinary turquoise waters. Its source is Mount Ishizuchi and it flows for just 77 miles.
As we’ve seen, the myriad rivers Japan has to offer play an important role in the country’s topography, ecology and its culture. Shaped by many centuries of geological and environmental forces as well as by human intervention, Japan’s waterways have in turn, shaped the country through which they flow.